diff --git a/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/TIMBotNetworkHandler.kt b/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/TIMBotNetworkHandler.kt
index 735ee9988..60317c017 100644
--- a/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/TIMBotNetworkHandler.kt
+++ b/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/TIMBotNetworkHandler.kt
@@ -3,7 +3,7 @@ package net.mamoe.mirai.network.protocol.tim
 import kotlinx.coroutines.*
 import kotlinx.coroutines.sync.Mutex
 import kotlinx.coroutines.sync.withLock
-import net.mamoe.mirai.Bot
+import net.mamoe.mirai.*
 import net.mamoe.mirai.event.ListeningStatus
 import net.mamoe.mirai.event.broadcast
 import net.mamoe.mirai.event.events.BeforePacketSendEvent
@@ -56,7 +56,7 @@ internal class TIMBotNetworkHandler(private val bot: Bot) : BotNetworkHandler {
     }
 
     //嵌套进 login 会导致 kotlin internal CompilationException
-    suspend fun loginInternal(ipQueue: LinkedList<String>): LoginState {
+    private suspend fun loginInternal(ipQueue: LinkedList<String>): LoginState {
         this.socket.close()
         val ip = ipQueue.poll() ?: return LoginState.UNKNOWN//所有服务器均返回 UNKNOWN
 
diff --git a/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/TIMProtocol.kt b/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/TIMProtocol.kt
index 84c23956c..5ded41a74 100644
--- a/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/TIMProtocol.kt
+++ b/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/TIMProtocol.kt
@@ -50,8 +50,6 @@ object TIMProtocol {
     const val constantData2 = "00 00 04 53 00 00 00 01 00 00 15 85 "
 
     /**
-     * 0825 key
-     *
      * Touch 发出时写入, 并用于加密, 接受 touch response 时解密.
      */
     const val touchKey = "A4 F1 91 88 C9 82 14 99 0C 9E 56 55 91 23 C8 3D"//16
@@ -62,12 +60,12 @@ object TIMProtocol {
     const val redirectionKey = "A8 F2 14 5F 58 12 60 AF 07 63 97 D6 76 B2 1A 3B"//16
 
     /**
-     *
+     * 并非常量. 设置为常量是为了让 [shareKey] 为常量
      */
     const val publicKey = "02 6D 28 41 D2 A5 6F D2 FC 3E 2A 1F 03 75 DE 6E 28 8F A8 19 3E 5F 16 49 D3"//25
 
     /**
-     * fix_0836_1
+     * 并非常量. 设置为常量是为了让 [shareKey] 为常量
      *
      * LoginResend 和 PasswordSubmission 时写入, 但随后都使用 shareKey 加密, 收到回复也是用的 share key
      */
@@ -79,7 +77,7 @@ object TIMProtocol {
     }
 
     /**
-     * 没有任何地方写入了这个 key
+     * 并非常量. 是 publicKey 与 key0836 的算法计算结果
      */
     //const val shareKey = "5B 6C 91 55 D9 92 F5 A7 99 85 37 76 3D 0F 08 B7"//16
     const val shareKey = "1A E9 7F 7D C9 73 75 98 AC 02 E0 80 5F A9 C6 AF"//16//original
diff --git a/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/GradeInfo.kt b/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/GradeInfo.kt
index 1c84c15ae..ff66c06d3 100644
--- a/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/GradeInfo.kt
+++ b/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/GradeInfo.kt
@@ -1,7 +1,6 @@
 package net.mamoe.mirai.network.protocol.tim.packet
 
 import net.mamoe.mirai.network.protocol.tim.TIMProtocol
-import net.mamoe.mirai.utils.TEA
 import java.io.DataInputStream
 
 /**
@@ -39,10 +38,6 @@ class ServerAccountInfoResponsePacket(input: DataInputStream) : ServerPacket(inp
 
     @PacketId("00 5C")
     class Encrypted(inputStream: DataInputStream) : ServerPacket(inputStream) {
-        fun decrypt(sessionKey: ByteArray): ServerAccountInfoResponsePacket {
-            this.input goto 14
-            val data = this.input.readAllBytes().let { it.copyOfRange(0, it.size - 1) }
-            return ServerAccountInfoResponsePacket(TEA.decrypt(data, sessionKey).dataInputStream()).setId(this.idHex)
-        }
+        fun decrypt(sessionKey: ByteArray): ServerAccountInfoResponsePacket = ServerAccountInfoResponsePacket(this.decryptBy(sessionKey)).setId(this.idHex)
     }
 }
\ No newline at end of file
diff --git a/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/ServerPacket.kt b/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/ServerPacket.kt
index 9b8cf15a0..677e2d100 100644
--- a/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/ServerPacket.kt
+++ b/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/ServerPacket.kt
@@ -179,6 +179,8 @@ abstract class ServerPacket(val input: DataInputStream) : Packet {
         input.goto(14)
         return TEA.decrypt(input.readAllBytes().cutTail(1), key)
     }
+
+    fun decryptAsByteArray(keyHex: String): ByteArray = this.decryptAsByteArray(keyHex.hexToBytes())
 }
 
 
@@ -243,7 +245,7 @@ fun ByteArray.dataInputStream(): DataInputStream = DataInputStream(this.inputStr
 /**
  * Reset and skip(position)
  */
-infix fun <N : Number> DataInputStream.goto(position: N): DataInputStream {
+fun <N : Number> DataInputStream.goto(position: N): DataInputStream {
     this.reset()
     this.skip(position.toLong())
     return this
diff --git a/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/login/SKey.kt b/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/login/SKey.kt
index 0e7c4f5fd..11154e532 100644
--- a/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/login/SKey.kt
+++ b/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/login/SKey.kt
@@ -2,7 +2,6 @@ package net.mamoe.mirai.network.protocol.tim.packet.login
 
 import net.mamoe.mirai.network.protocol.tim.TIMProtocol
 import net.mamoe.mirai.network.protocol.tim.packet.*
-import net.mamoe.mirai.utils.TEA
 import java.io.DataInputStream
 
 
@@ -58,10 +57,6 @@ class ServerSKeyResponsePacket(input: DataInputStream) : ServerPacket(input) {
 
 
     class Encrypted(inputStream: DataInputStream) : ServerPacket(inputStream) {
-        fun decrypt(sessionKey: ByteArray): ServerSKeyResponsePacket {
-            this.input goto 14
-            val data = this.input.readAllBytes().let { it.copyOfRange(0, it.size - 1) }
-            return ServerSKeyResponsePacket(TEA.decrypt(data, sessionKey).dataInputStream()).setId(this.idHex)
-        }
+        fun decrypt(sessionKey: ByteArray): ServerSKeyResponsePacket = ServerSKeyResponsePacket(this.decryptBy(sessionKey)).setId(this.idHex)
     }
 }
\ No newline at end of file
diff --git a/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/login/ServerLoginResponsePasswordVerifiedPacket.kt b/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/login/ServerLoginResponsePasswordVerifiedPacket.kt
index 8af0fb0f2..36574abfe 100644
--- a/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/login/ServerLoginResponsePasswordVerifiedPacket.kt
+++ b/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/login/ServerLoginResponsePasswordVerifiedPacket.kt
@@ -55,7 +55,7 @@ class ServerLoginResponseSuccessPacket(input: DataInputStream) : ServerPacket(in
     class Encrypted(input: DataInputStream) : ServerPacket(input) {
 
         fun decrypt(privateKey: ByteArray): ServerLoginResponseSuccessPacket {
-            input goto 14
+            input.goto(14)
             return ServerLoginResponseSuccessPacket(this.decryptBy(TIMProtocol.shareKey, privateKey)).setId(this.idHex)
         }
     }
diff --git a/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/login/ServerLoginResponseVerificationCodeInitPacket.kt b/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/login/ServerLoginResponseVerificationCodeInitPacket.kt
index 8c44a012a..5c07854e8 100644
--- a/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/login/ServerLoginResponseVerificationCodeInitPacket.kt
+++ b/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/login/ServerLoginResponseVerificationCodeInitPacket.kt
@@ -40,16 +40,14 @@ class ServerLoginResponseVerificationCodeInitPacket(input: DataInputStream, priv
 
         }
 
-        fun decrypt(): ServerLoginResponseVerificationCodeInitPacket {
-            this.input goto 14
-            val data = this.decryptBy(TIMProtocol.shareKey).goto(0).readAllBytes()
-            return ServerLoginResponseVerificationCodeInitPacket(data.dataInputStream(), data.size).setId(this.idHex)
+        fun decrypt(): ServerLoginResponseVerificationCodeInitPacket = this.decryptAsByteArray(TIMProtocol.shareKey).let {
+            ServerLoginResponseVerificationCodeInitPacket(it.dataInputStream(), it.size).setId(this.idHex)
         }
     }
 }
 
 fun main() {
-    val data = "FB 01 04 03 33 00 01 00 BA 02 03 2C 13 00 05 01 00 00 01 23 00 38 D5 01 05 8B 67 4D 52 5A FA 92 DB 99 18 D4 F0 72 03 E0 17 71 7C 8A 45 74 1F C3 2D F8 61 96 0D 93 0D 8C 51 95 70 F8 F9 CB B9 2D 5D BC 4F 5D 89 5F E7 59 8C E4 E5 A2 04 56 02 BC 89 50 4E 47 0D 0A 1A 0A 00 00 00 0D 49 48 44 52 00 00 00 82 00 00 00 35 08 03 00 00 00 BA 12 C3 02 00 00 00 04 67 41 4D 41 00 00 B1 8F 0B FC 61 05 00 00 00 01 73 52 47 42 00 AE CE 1C E9 00 00 00 45 50 4C 54 45 FE F6 ED E2 F1 DF F3 FF F2 11 77 48 FE FE F3 F1 F9 EA D7 FD E7 F8 F9 EC FC EF E7 E8 FF EE 2D 69 48 2A 8A 5D 29 7A 52 F0 ED E1 A9 C7 B1 65 96 79 AB E0 C2 C3 F0 D5 42 7D 5C 4A 99 72 89 AA 93 51 73 5C 6E BA 94 42 BD 7A 0B 00 00 09 C5 49 44 41 54 58 C3 AC 99 8B 76 AB 3A 12 44 91 D0 1B 10 08 04 FF FF A9 B3 5B 60 C7 AF 38 77 EE 0C EB C4 76 6C 07 95 BA AB AB AB 75 BA EE 1F 5D DE CB 63 08 C1 C7 A8 AD BC B6 31 46 6B 3B A3 79 94 E7 F3 63 79 E4 D9 98 89 37 7D F7 FF BB 3C 10 82 6F B7 F7 2A B6 5B 07 EF B5 16 60 DE 1B 63 3A 1F 7E BE 6D 0C 50 EC 09 E1 FE 76 B8 3F FC 6B 0C 1D 5B 37 1F 3E E1 AE 61 9A D8 B6 07 93 B7 56 4D 66 22 06 9D FC EE 5F BF F9 3F 81 90 BB 99 F3 49 E2 1D DA 43 38 13 44 14 8C 9D B4 8E E7 65 40 11 E4 BB FE 8C 5B 78 41 F1 AF 01 48 2E 08 6D 8B AD F1 BA 05 F9 C4 E0 25 E6 31 BA EB 2A 90 C3 74 26 FC 1E 80 CF 14 91 44 7F FC 39 FF D4 37 10 82 C0 B3 B0 67 BF 2E 5E 5B F4 46 E5 3A 5F D7 BE A6 54 17 2D 7C 0D D7 DA E1 7E 93 C7 E5 DB 9E 6E 9F FD A3 14 9C 7F 23 97 55 FA DC 6F 74 8A CC 04 49 03 3F DE 4E 5C 4A 95 9C 53 8D 7A EA 82 F9 10 77 7F EE E5 43 28 C2 9F 00 BA 5B C0 59 A4 CE DB BA AE DB BC 14 D5 2A 82 A5 83 E0 30 92 19 A8 99 36 A7 15 7C BC DF F6 BE D7 86 C0 7F C9 C5 ED 93 C7 1F B9 E0 56 CB AC 61 F5 5D 2E 00 F0 93 D2 5A 9D B6 B0 3F 4B 4D 5C B9 0F C1 EE 29 46 65 4E 40 46 E2 E4 1B 91 C3 A5 2E FE D3 7A 3C 84 0B E3 F3 E2 57 16 2F 08 B9 E6 5A 73 29 65 29 4E B9 25 CF 6B 9A 97 48 20 B2 35 46 1B 6D AD D6 9A 57 69 45 B2 1A 00 90 05 51 8D C7 24 F8 1B B9 FE A6 41 B8 83 6C 59 05 84 9F 44 0F 85 05 9A 97 5A 97 BC A6 6D 81 FE 59 DE 2F 4B 5E E4 DF B2 A4 19 AA 06 D9 FE F9 33 4D 7E 6A 40 FC 97 34 BF 84 E4 81 81 ED E9 DC 85 32 56 47 E5 A4 F0 2D 6F 4D 2A BA 65 4B 73 89 B6 58 5E D7 35 8D 69 E4 4A 6B 76 50 C1 5C 3A D9 59 11 CF 37 99 FA 48 88 70 7F F4 9F 22 12 F2 24 91 3E 2B BF 28 A5 34 68 C0 50 A3 55 DD A4 E3 9C 6E 85 99 95 B6 24 2E 18 D9 3C 5C B1 4D AA 2F 08 E1 75 F1 F0 6B 49 FC BC E3 8D 00 01 00 28 42 E6 18 57 D4 B1 4D AE 51 27 D5 EF A2 38 91 39 15 37 6C 5A FE 75 93 49 DB FC 57 3C 12 3F 26 D9 16 1D 83 45 8B 78 39 D8 01 15 00 10 F6 F0 50 03 74 BB 18 91 D3 55 8D 7F BB 53 15 7A".hexToUBytes().toByteArray();
+    val data = "FB 01 04 03 33 00 01 00 BA 02 03 2C 13 00 05 01 00 00 01 23 00 38 D5 01 05 8B 67 4D 52 5A FA 92 DB 99 18 D4 F0 72 03 E0 17 71 7C 8A 45 74 1F C3 2D F8 61 96 0D 93 0D 8C 51 95 70 F8 F9 CB B9 2D 5D BC 4F 5D 89 5F E7 59 8C E4 E5 A2 04 56 02 BC 89 50 4E 47 0D 0A 1A 0A 00 00 00 0D 49 48 44 52 00 00 00 82 00 00 00 35 08 03 00 00 00 BA 12 C3 02 00 00 00 04 67 41 4D 41 00 00 B1 8F 0B FC 61 05 00 00 00 01 73 52 47 42 00 AE CE 1C E9 00 00 00 45 50 4C 54 45 FE F6 ED E2 F1 DF F3 FF F2 11 77 48 FE FE F3 F1 F9 EA D7 FD E7 F8 F9 EC FC EF E7 E8 FF EE 2D 69 48 2A 8A 5D 29 7A 52 F0 ED E1 A9 C7 B1 65 96 79 AB E0 C2 C3 F0 D5 42 7D 5C 4A 99 72 89 AA 93 51 73 5C 6E BA 94 42 BD 7A 0B 00 00 09 C5 49 44 41 54 58 C3 AC 99 8B 76 AB 3A 12 44 91 D0 1B 10 08 04 FF FF A9 B3 5B 60 C7 AF 38 77 EE 0C EB C4 76 6C 07 95 BA AB AB AB 75 BA EE 1F 5D DE CB 63 08 C1 C7 A8 AD BC B6 31 46 6B 3B A3 79 94 E7 F3 63 79 E4 D9 98 89 37 7D F7 FF BB 3C 10 82 6F B7 F7 2A B6 5B 07 EF B5 16 60 DE 1B 63 3A 1F 7E BE 6D 0C 50 EC 09 E1 FE 76 B8 3F FC 6B 0C 1D 5B 37 1F 3E E1 AE 61 9A D8 B6 07 93 B7 56 4D 66 22 06 9D FC EE 5F BF F9 3F 81 90 BB 99 F3 49 E2 1D DA 43 38 13 44 14 8C 9D B4 8E E7 65 40 11 E4 BB FE 8C 5B 78 41 F1 AF 01 48 2E 08 6D 8B AD F1 BA 05 F9 C4 E0 25 E6 31 BA EB 2A 90 C3 74 26 FC 1E 80 CF 14 91 44 7F FC 39 FF D4 37 10 82 C0 B3 B0 67 BF 2E 5E 5B F4 46 E5 3A 5F D7 BE A6 54 17 2D 7C 0D D7 DA E1 7E 93 C7 E5 DB 9E 6E 9F FD A3 14 9C 7F 23 97 55 FA DC 6F 74 8A CC 04 49 03 3F DE 4E 5C 4A 95 9C 53 8D 7A EA 82 F9 10 77 7F EE E5 43 28 C2 9F 00 BA 5B C0 59 A4 CE DB BA AE DB BC 14 D5 2A 82 A5 83 E0 30 92 19 A8 99 36 A7 15 7C BC DF F6 BE D7 86 C0 7F C9 C5 ED 93 C7 1F B9 E0 56 CB AC 61 F5 5D 2E 00 F0 93 D2 5A 9D B6 B0 3F 4B 4D 5C B9 0F C1 EE 29 46 65 4E 40 46 E2 E4 1B 91 C3 A5 2E FE D3 7A 3C 84 0B E3 F3 E2 57 16 2F 08 B9 E6 5A 73 29 65 29 4E B9 25 CF 6B 9A 97 48 20 B2 35 46 1B 6D AD D6 9A 57 69 45 B2 1A 00 90 05 51 8D C7 24 F8 1B B9 FE A6 41 B8 83 6C 59 05 84 9F 44 0F 85 05 9A 97 5A 97 BC A6 6D 81 FE 59 DE 2F 4B 5E E4 DF B2 A4 19 AA 06 D9 FE F9 33 4D 7E 6A 40 FC 97 34 BF 84 E4 81 81 ED E9 DC 85 32 56 47 E5 A4 F0 2D 6F 4D 2A BA 65 4B 73 89 B6 58 5E D7 35 8D 69 E4 4A 6B 76 50 C1 5C 3A D9 59 11 CF 37 99 FA 48 88 70 7F F4 9F 22 12 F2 24 91 3E 2B BF 28 A5 34 68 C0 50 A3 55 DD A4 E3 9C 6E 85 99 95 B6 24 2E 18 D9 3C 5C B1 4D AA 2F 08 E1 75 F1 F0 6B 49 FC BC E3 8D 00 01 00 28 42 E6 18 57 D4 B1 4D AE 51 27 D5 EF A2 38 91 39 15 37 6C 5A FE 75 93 49 DB FC 57 3C 12 3F 26 D9 16 1D 83 45 8B 78 39 D8 01 15 00 10 F6 F0 50 03 74 BB 18 91 D3 55 8D 7F BB 53 15 7A".hexToUBytes().toByteArray()
     ServerLoginResponseVerificationCodeInitPacket(
             data.dataInputStream(),
             data.size
diff --git a/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/login/Session.kt b/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/login/Session.kt
index 349b15b64..c2544f651 100644
--- a/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/login/Session.kt
+++ b/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/login/Session.kt
@@ -2,7 +2,6 @@ package net.mamoe.mirai.network.protocol.tim.packet.login
 
 import net.mamoe.mirai.network.protocol.tim.TIMProtocol
 import net.mamoe.mirai.network.protocol.tim.packet.*
-import net.mamoe.mirai.utils.TEA
 import net.mamoe.mirai.utils.dataEncode
 import java.io.DataInputStream
 import java.net.InetAddress
@@ -74,7 +73,7 @@ class ServerSessionKeyResponsePacket(inputStream: DataInputStream, private val d
     override fun decode() {
         when (dataLength) {
             407 -> {
-                input goto 25
+                input.goto(25)
                 sessionKey = input.readNBytes(16)
             }
 
@@ -106,10 +105,8 @@ class ServerSessionKeyResponsePacket(inputStream: DataInputStream, private val d
     }
 
     class Encrypted(inputStream: DataInputStream) : ServerPacket(inputStream) {
-        fun decrypt(sessionResponseDecryptionKey: ByteArray): ServerSessionKeyResponsePacket {
-            this.input goto 14
-            val data = this.input.readAllBytes().let { it.copyOfRange(0, it.size - 1) }
-            return ServerSessionKeyResponsePacket(TEA.decrypt(data, sessionResponseDecryptionKey).dataInputStream(), data.size).setId(this.idHex)
+        fun decrypt(sessionResponseDecryptionKey: ByteArray): ServerSessionKeyResponsePacket = this.decryptAsByteArray(sessionResponseDecryptionKey).let {
+            ServerSessionKeyResponsePacket(it.dataInputStream(), it.size).setId(this.idHex)
         }
     }
 }
\ No newline at end of file
diff --git a/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/login/VerificationCode.kt b/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/login/VerificationCode.kt
index c54a2dccc..19d49c1a9 100644
--- a/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/login/VerificationCode.kt
+++ b/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/network/protocol/tim/packet/login/VerificationCode.kt
@@ -2,10 +2,7 @@ package net.mamoe.mirai.network.protocol.tim.packet.login
 
 import net.mamoe.mirai.network.protocol.tim.TIMProtocol
 import net.mamoe.mirai.network.protocol.tim.packet.*
-import net.mamoe.mirai.utils.TEA
 import net.mamoe.mirai.utils.Tested
-import net.mamoe.mirai.utils.cutTail
-import net.mamoe.mirai.utils.hexToBytes
 import java.io.DataInputStream
 
 /**
@@ -192,8 +189,7 @@ abstract class ServerCaptchaPacket(input: DataInputStream) : ServerPacket(input)
     class Encrypted(input: DataInputStream, private val id: String) : ServerPacket(input) {
 
         fun decrypt(): ServerCaptchaPacket {
-            this.input goto 14
-            val data = TEA.decrypt(this.input.readAllBytes().cutTail(1), TIMProtocol.key00BA.hexToBytes())
+            val data = this.decryptAsByteArray(TIMProtocol.key00BA)
             if (id.startsWith("00 BA 32")) {
                 return when (data.size) {
                     66,
diff --git a/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/utils/CharImageUtil.kt b/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/utils/CharImageUtil.kt
index cc1dee354..e73e32716 100644
--- a/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/utils/CharImageUtil.kt
+++ b/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/utils/CharImageUtil.kt
@@ -6,6 +6,6 @@ import java.awt.image.BufferedImage
  * @author NaturalHG
  */
 @JvmOverloads
-fun BufferedImage.createCharImg(sizeWeight: Int = 100, sizeHeight: Int = 20): String {
+fun BufferedImage.createCharImg(sizeWeight: Int = 100): String {
     return CharImageConverter(this, sizeWeight).call()
 }
\ No newline at end of file
diff --git a/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/utils/setting/MiraiSettingMapSection.kt b/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/utils/setting/MiraiSettingMapSection.kt
index e5db92ce0..a44f5345b 100644
--- a/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/utils/setting/MiraiSettingMapSection.kt
+++ b/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/utils/setting/MiraiSettingMapSection.kt
@@ -2,10 +2,8 @@ package net.mamoe.mirai.utils.setting
 
 
 import org.ini4j.Profile
-
 import java.io.IOException
 import java.util.concurrent.ConcurrentHashMap
-import java.util.stream.Collectors
 import kotlin.streams.toList
 
 
@@ -19,6 +17,7 @@ class MiraiSettingMapSection : ConcurrentHashMap<String, Any>(), MiraiSettingSec
             return defaultValue
         }
         return if (super.containsKey(key)) {
+            @Suppress("UNCHECKED_CAST")
             super.get(key) as T
         } else defaultValue
     }
@@ -28,10 +27,6 @@ class MiraiSettingMapSection : ConcurrentHashMap<String, Any>(), MiraiSettingSec
         this[key] = value
     }
 
-    override fun remove(key: String) {
-        super.remove(key)
-    }
-
     fun getInt(key: String): Int {
         return this.getInt(key, 0)
     }
diff --git a/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/utils/setting/MiraiSettings.kt b/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/utils/setting/MiraiSettings.kt
index 480640798..4b79f0cf1 100644
--- a/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/utils/setting/MiraiSettings.kt
+++ b/mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/utils/setting/MiraiSettings.kt
@@ -14,13 +14,12 @@ import java.util.concurrent.ConcurrentHashMap
  *
  * @author NaturalHG
  */
-class MiraiSettings
+class MiraiSettings(file: File)
 /*
     public MiraiSettings(MiraiPluginBase pluginBase, String filename) {
         // TODO: 2019/9/6 每个插件独立文件夹存放
         this(new File(filename));
-    }*/
-(file: File) {
+    }*/ {
 
     private val file: File
 
@@ -29,14 +28,10 @@ class MiraiSettings
     private val cacheSection = ConcurrentHashMap<String, MiraiSettingSection>()
 
     init {
-        var file = file
-        Objects.requireNonNull(file)
-        if (!file.name.contains(".")) {
-            file = File(file.path + ".ini")
-        }
-        this.file = file
-        if (!file.exists() && !file.createNewFile()) {
-            throw RuntimeException("cannot create config file $file")
+        val f = file.takeIf { it.name.contains(".") } ?: File(file.path + ".ini")
+        this.file = f
+        if (!f.exists() && !f.createNewFile()) {
+            throw RuntimeException("cannot create config file $f")
         }
         val config = Config()
         config.isMultiSection = true